JP6922799B2 - Vehicle control device - Google Patents

Description

The present invention relates to a control device for a vehicle provided with a stepped automatic transmission, and more particularly to a technique for returning from coasting running in which the engine and wheels are separated to normal running in which the engine and wheels are connected. ..

A stepped automatic transmission having a plurality of engaging elements and realizing a plurality of gears by changing a combination of a predetermined number of, for example, a pair of engaging elements among the plurality of engaging elements is provided. In the vehicle, for example, in the D range (normal driving range by automatic transmission of all gears), when the accelerator pedal is released while driving, the transmission is set to the neutral state and the power transmission path is released, and the vehicle is coasted. Engagement elements such as adjusting the hydraulic pressure of the engagement element for forming the gear so that the gear can be immediately formed according to the vehicle speed when the accelerator pedal is depressed after the vehicle is driven. Is being prepared. For example, it is a vehicle control device provided with a stepped automatic transmission described in paragraph 0004 of Patent Document 1.

Japanese Unexamined Patent Publication No. 2012-215211

By the way, in a vehicle control device equipped with a stepped automatic transmission as described above, after the driver depresses the accelerator, no driving force is generated until the stepped step is formed. If there is a large discrepancy between the input rotation speed of the automatic transmission and the synchronous rotation speed of the target gear, there is a problem that it takes a long time to form the target gear and a feeling of sluggishness is felt until reacceleration. rice field.

The present invention has been made in the background of the above circumstances, and an object of the present invention is to promptly depress the accelerator when the driver depresses the accelerator during coasting while the transmission is in the neutral state. It is an object of the present invention to provide a vehicle control device provided with a stepped automatic transmission capable of generating a driving force.

The gist of the first invention is that (a) a plurality of engaging elements are provided, and a plurality of shift stages are formed by changing a combination of a predetermined number of engaging elements among the plurality of engaging elements. It is applied to vehicles equipped with a stepped automatic transmission, and when coasting by releasing the access pedal, one of the predetermined number of engaging elements is released to put the stepped automatic transmission in the neutral state. When returning from the coasting by depressing the accelerator pedal, the control device of the vehicle provided with a stepped automatic transmission for returning from the coasting by forming a target shift stage corresponding to the vehicle running state. Therefore, (b) when returning from the coasting operation by depressing the accelerator pedal, a selective shift gear having a synchronous rotation speed lower than the actual input rotation speed of the stepped automatic transmission is selected, and the selection is made. The target is the first engagement control unit that increases the engagement force of the engagement element forming the shift stage to immediately increase the driving force of the vehicle, and (c) the actual input rotation speed of the stepped automatic transmission. When the determination rotation speed set for determining that the synchronous rotation speed of the shift stage has been reached is reached, the second engagement control unit that engages the engagement element forming the target shift speed is included. It is in.

The gist of the second invention is that in the control device of the vehicle provided with the stepped automatic transmission of the first invention, (d) the first engagement control unit is an actual stepped automatic transmission. Among the gears having a synchronous rotation speed lower than the input rotation speed, the gear on the slowest speed side is the selected gear.

The gist of the third invention is that the first engagement control unit limits the selected gear so as not to be a gear on the lower speed side than the target gear.

The gist of the fourth invention is that the actual input rotation speed of the stepped automatic transmission is lower than the synchronous rotation speed of the maximum speed shift when returning from coasting by depressing the accelerator pedal. In the case of, the first engagement control unit selects the selected shift stage until the actual input rotation speed of the stepped automatic transmission becomes equal to or higher than the synchronous rotation speed of the maximum speed side shift stage. Delay.

The gist of the fifth invention is that the target shift stage is based on the actual vehicle speed and the required drive amount at the time of returning from the coasting by the depression operation of the accelerator pedal from the shift line diagram stored in advance. It is to be decided.

According to the control device of the vehicle provided with the stepped automatic transmission of the first invention, when returning from the coasting by the depression operation of the accelerator pedal, the stepped automatic transmission is performed by the first engagement control unit. A selective speed change having a synchronous speed lower than the actual input speed of the machine is selected, and the engaging force of the engaging elements forming the selective speed change is increased to immediately increase the driving force of the vehicle, and then the driving force of the vehicle is increased immediately. When the second engagement control unit reaches the determination rotation speed set for determining that the actual input rotation speed of the stepped automatic transmission has reached the synchronous rotation speed of the target transmission speed, the above-mentioned The engaging elements that form the target speed are engaged. As a result, the engaging force of the engaging element forming the selected gear is increased, the driving force of the vehicle is immediately increased, and the input rotation speed of the stepped automatic transmission is synchronized with the target gear. Since the target shift stage is formed after the deviation from the number of revolutions is reduced, the driving force is quickly generated when the driver depresses the accelerator during coasting with the transmission in the neutral state. be able to.

According to the control device of the vehicle provided with the stepped automatic transmission of the second invention, the first engagement control unit has a synchronous rotation speed lower than the actual input rotation speed of the stepped automatic transmission. Among the gears, the gear on the slowest speed side is the selected gear. As a result, even if the deviation between the input rotation speed of the stepped automatic transmission and the synchronous rotation speed of the target transmission speed is large, the driving force of the vehicle can be immediately increased and the deviation can be reduced as much as possible. Since the target shift stage is formed, the driving force can be generated more quickly when the driver depresses the accelerator during coasting while the transmission is in the neutral state.

According to the control device of the vehicle provided with the stepped automatic transmission of the third invention, the first engagement control unit prevents the selected gear from being a gear at a lower speed than the target gear. Since this is a limitation, the input rotation speed can be smoothly increased toward the synchronous rotation speed of the target shift stage in a short time after the coasting is completed.

According to the control device of the vehicle provided with the stepped automatic transmission of the fourth invention, the actual input rotation speed of the stepped automatic transmission is the highest when returning from coasting by depressing the accelerator pedal. When the rotation speed is lower than the synchronous rotation speed of the high-speed shift stage, the first engagement control unit has the actual input rotation speed of the stepped automatic transmission equal to or higher than the synchronous rotation speed of the maximum speed side shift stage. The selection of the selected shift stage is delayed until As a result, in high-speed coasting with the automatic transmission 22 in the neutral state, the maximum speed side shift stage is selected after the input rotation speed of the automatic transmission 22 becomes equal to or higher than the synchronous rotation speed of the maximum speed side shift stage. The engaging force of the engaging element forming the selective shift stage is increased.

According to the control device of the vehicle provided with the stepped automatic transmission of the fifth invention, the target shift stage is obtained from the gear shift diagram stored in advance when returning from the coasting operation by depressing the accelerator pedal. Since it is determined based on the actual vehicle speed and drive demand in the above, the driver can switch from coasting with the transmission in the neutral state to the target shift stage according to the actual vehicle speed and drive demand. The driving force can be quickly generated according to the depression operation of the accelerator.

It is a figure explaining the schematic structure of the vehicle to which this invention is applied, and also is the figure explaining the main part of the control function of the electronic control device for various control in a vehicle. It is a skeleton diagram explaining an example of a torque converter and an automatic transmission. It is an operation chart explaining the relationship between the shift operation of an automatic transmission and the operation of the engaging element used therein. This is an example of a shift line diagram used for switching the shift stage of the automatic transmission of FIG. 1. It is a time chart explaining the main part of the control operation of the electronic control device of FIG. It is a flowchart explaining the main part of the control operation of the electronic control device of FIG. It is a time chart explaining the main part of the control operation of the conventional electronic control device.

Hereinafter, examples of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram for explaining a schematic configuration of a vehicle 10 to which the present invention is applied, and is a diagram for explaining a main part of a control function of an electronic control device 70 provided in the vehicle 10. In FIG. 1, the vehicle 10 includes an engine 12, drive wheels 14, and a power transmission device 16 provided in a power transmission path between the engine 12 and the drive wheels 14.

The power transmission device 16 is a reduction gear connected to a torque converter 20, an automatic transmission 22, and a transmission output gear 24 which is an output rotating member of the automatic transmission 22 in a case 18 as a non-rotating member attached to a vehicle body. It includes a mechanism 26, a differential gear (differential gear device) 28 connected to the reduction gear mechanism 26, and the like. Further, the power transmission device 16 includes a pair of drive shafts (axles) 30 and the like connected to the differential gear 28. In the power transmission device 16, the power output from the engine 12 (torque and force are synonymous unless otherwise specified) includes a torque converter 20, an automatic transmission 22, a reduction gear mechanism 26, a differential gear 28, a drive shaft 30, and the like. Is sequentially transmitted to the drive wheels 14.

The engine 12 is a power source for the vehicle 10 and is a known internal combustion engine such as a gasoline engine or a diesel engine. The engine torque Te of the engine 12 is controlled by controlling the operating state such as the intake air amount, the fuel injection amount, and the ignition timing according to the operation amount of the accelerator pedal 68 by the electronic control device 70 described later.

FIG. 2 is a skeleton diagram illustrating an example of a torque converter 20 and an automatic transmission 22. The torque converter 20, the automatic transmission 22, and the like are configured substantially symmetrically with respect to the axial center RC of the transmission input shaft 32, which is an input rotating member of the automatic transmission 22, and in FIG. 2, the axial center RC is configured. The lower half is omitted.

In FIG. 2, the torque converter 20 is arranged so as to rotate around the axis RC in the power transmission path between the engine 12 and the automatic transmission 22, such as a pump impeller 20p and a turbine impeller 20t. It is a fluid type transmission device equipped with. The pump impeller 20p is an input rotating member of the torque converter 20 and is connected to the engine 12. The turbine impeller 20t is an output rotating member of the torque converter 20, and is connected to the transmission input shaft 32. The transmission input shaft 32 is also a turbine shaft that is rotationally driven by the turbine impeller 20t. Further, the torque converter 20 includes a known lockup clutch LC as a direct-coupled clutch that connects the pump impeller 20p and the turbine impeller 20t (that is, connects the input / output rotating members of the torque converter 20). Further, the power transmission device 16 includes a mechanical oil pump 34 connected to the pump impeller 20p.

The oil pump 34 is rotationally driven by the engine 12 and is used for shift control of the automatic transmission 22 or for switching control of the operating state of the lockup clutch LC. Lubricating oil is applied to each part of the power transmission device 16. Discharges hydraulic oil for supply. That is, the hydraulic oil pumped by the oil pump 34 is supplied as the main pressure of the hydraulic control circuit 50 (see FIG. 1) provided in the vehicle 10.

The lockup clutch LC is a hydraulic friction clutch that is frictionally engaged by being supplied with an engaging oil pressure (also referred to as LC hydraulic pressure) from the hydraulic control circuit 50. The operating state of the lockup clutch LC is switched by controlling the LC hydraulic pressure by the electronic control device 70 described later. The operating states of the lockup clutch LC include a lockup released state in which the lockup clutch LC is released, a slip state in which the lockup clutch LC is slipped with slipping, and a lockup clutch LC is engaged (locked up). ) There is a lockup state.

When the lockup clutch LC is released, the torque converter 20 can obtain a torque amplification action. Further, when the lockup clutch LC is engaged, the pump impeller 20p and the turbine impeller 20t are integrally rotated, and the power of the engine 12 is directly transmitted to the automatic transmission 22 side. Further, the lockup clutch LC is slip-operated so that the slip amount Ns (= engine speed Ne-turbine speed Nt; also referred to as slip speed or difference speed) in the lockup clutch LC becomes the target slip amount Nst. As a result, when the vehicle 10 is driven (power on), the engine speed Ne is suppressed from rising and noise such as muffled noise is suppressed, while when the vehicle 10 is not driven (power off), the target slip is suppressed. The engine 12 is rotated following the transmission input shaft 32 at the amount Nst, and the fuel cut region is expanded, for example.

In FIG. 2, the automatic transmission 22 is a stepped automatic transmission that forms a part of a power transmission path between the engine 12 and the drive wheels 14. The automatic transmission 22 is coaxial with the double pinion type first planetary gear device 36, the single pinion type second planetary gear device 38, and the double pinion type third planetary gear device 40, which are configured in a labinyo type. It is a planetary gear type multi-speed transmission on the line (on the axis RC). The automatic transmission 22 is a plurality of engaging devices of the first clutch C1, the second clutch C2, the third clutch C3, the fourth clutch C4, the first brake B1, and the second brake B2 (hereinafter, unless otherwise specified). It simply has an engaging element CB).

The first planetary gear device 36 includes a first sun gear S1, a plurality of pairs of first planetary gears P1a and P1b that mesh with each other, and a first carrier CA1 that supports the first planetary gears P1a and P1b so as to rotate and revolve. It includes a first ring gear R1 that meshes with the first sun gear S1 via the first planetary gears P1a and P1b. The second planetary gear device 38 includes a second sun gear S2, a second planet gear P2, a carrier RCA that supports the second planet gear P2 so as to rotate and revolve, and a second sun gear via the second planet gear P2. It is equipped with a ring gear RR that meshes with S2. The third planetary gear device 40 includes a third sun gear S3, a plurality of pairs of third planetary gears P3a and P3b that mesh with each other, a carrier RCA that supports the third planetary gears P3a and P3b so as to rotate and revolve, and a third planetary gear. It includes a ring gear RR that meshes with the third sun gear S3 via planetary gears P3a and P3b. In the second planetary gear device 38 and the third planetary gear device 40, the third planetary gear P3b is shared with the second planetary gear P2, and the carrier is composed of a common carrier RCA and the ring gear is a common ring gear. It is a so-called labigno type composed of RR.

The engaging element CB is a hydraulic friction engaging device composed of a wet multi-plate clutch, a brake, or the like pressed by a hydraulic actuator. The engaging element CB is each hydraulic pressure (clutch pressure) Pc (that is, clutch pressure Pc1, Pc2, Pc3, Pc4, Pb1, as an engaging pressure output from each solenoid valve SL1-SL6 or the like in the hydraulic control circuit 50. By changing each torque capacity (clutch torque) Tc (that is, clutch torques Tc1, Tc2, Tc3, Tc4, Tb1, Tb2) by Pb2), the operating states (states such as engagement and disengagement) can be switched. .. Torque, for example, is input to the transmission input shaft 32 between the transmission input shaft 32 and the transmission output gear 24 without sliding the engagement element CB (that is, without causing a difference in rotation speed in the engagement element CB). In order to transmit the input torque Ti (that is, the turbine torque Tt), the torque that the transmission torque that each engaging element CB needs to take charge of (that is, the shared torque of the engaging element CB) is obtained. Capacity is required.

In the automatic transmission 22, the first sun gear S1 is connected to the case 18. The first carrier CA1 is connected to the transmission input shaft 32. The first carrier CA1 and the second sun gear S2 are selectively connected via the fourth clutch C4. The first ring gear R1 and the third sun gear S3 are selectively connected via the first clutch C1. The first ring gear R1 and the second sun gear S2 are selectively connected via a third clutch C3. The second sun gear S2 is selectively connected to the case 18 via the first brake B1. The carrier RCA is selectively connected to the transmission input shaft 32 via the second clutch C2. The carrier RCA is selectively coupled to the case 18 via the second brake B2. The ring gear RR is connected to the transmission output gear 24.

In the automatic transmission 22, the gear ratio (shifting) is obtained by selectively engaging any two of the engaging elements CB according to the driver's accelerator operation, vehicle speed V, etc. by the electronic control device 70 described later. This is a stepped transmission in which a plurality of gear stages (shift stages) Gn having different γ (= input rotation speed Nin of the automatic transmission 22 / output rotation speed Nout of the automatic transmission 22) are selectively formed. As shown in the engagement operation table of FIG. 3, for example, the automatic transmission 22 has eight forward gears of the first gear "1st" -8th gear "8th" and the reverse gear "Rev". Each gear stage Gn is selectively formed. The input rotation speed Nin of the automatic transmission 22 is the rotation speed (rotational speed) of the transmission input shaft 32, and the output rotation speed Now of the automatic transmission 22 is the rotation speed (rotational speed) of the transmission output gear 24. ). The gear ratio γ of the automatic transmission 22 corresponding to each gear stage Gn is the gear ratio of each of the first planetary gear device 36, the second planetary gear device 38, and the third planetary gear device 40 (= number of sun gear teeth / ring gear). The number of teeth) ρ1, ρ2, ρ3 as appropriate. The gear ratio γ of the 1st gear stage “1st” is the largest, and becomes smaller toward the higher vehicle speed side (8th gear stage “8th” side).

The engagement operation table of FIG. 3 summarizes the relationship between each gear stage Gn formed by the automatic transmission 22 and each operation state of the engagement element CB. Each represents liberation. In FIG. 3, the shift stage Gn is established by the engagement of the two engaging elements. For example, in the forward gear stage, the first speed gear stage "1st" is established by engaging the first clutch C1 and the second brake B2. The second speed gear stage "2nd" is established by the engagement between the first clutch C1 and the first brake B1. The third speed gear stage "3rd" is established by the engagement between the first clutch C1 and the third clutch C3. The fourth speed gear stage "4th" is established by the engagement between the first clutch C1 and the fourth clutch C4. The fifth speed gear stage "5th" is established by the engagement between the first clutch C1 and the second clutch C2. The sixth speed gear stage "6th" is established by the engagement between the second clutch C2 and the fourth clutch C4. The seventh speed gear stage "7th" is established by the engagement between the second clutch C2 and the third clutch C3. The eighth speed gear stage "8th" is established by the engagement between the second clutch C2 and the first brake B1. Further, the reverse gear stage "Rev" is established by the engagement between the third clutch C3 and the second brake B2. Further, when none of the engaging elements CB are engaged or only one is engaged, the automatic transmission 22 is in a neutral state in which no gear stage is formed (that is, a neutral state in which power transmission is cut off). Will be done. That is, the automatic transmission 20 can be put into the neutral state by releasing the engaging element of any one of the engaging elements CB which is in the engaging state in each gear stage Gn.

Returning to FIG. 1, the vehicle 10 includes an electronic control device 70 as a controller including a control device of the vehicle 10 related to control of, for example, an engaging element CB. The electronic control device 70 includes, for example, a so-called microcomputer provided with a CPU, a RAM, a ROM, an input / output interface, and the like, and the CPU follows a program stored in the ROM in advance while using the temporary storage function of the RAM. Various controls of the vehicle 10 are executed by performing signal processing. The electronic control device 70 is separately configured for engine control, hydraulic control, and the like, if necessary.

The electronic control device 70 includes various sensors provided in the vehicle 10, such as an engine rotation speed sensor 52, an input rotation speed sensor 54, an output rotation speed sensor 56, an accelerator opening sensor 58, a throttle valve opening sensor 60, and a brake. Various signals based on the values detected by the switch 62, the shift position sensor 64, the oil temperature sensor 66, and the like are supplied. The various signals are, for example, the engine speed Ne, the input speed Nin which is also the turbine shaft speed (that is, the turbine speed Nt), the output speed Nout corresponding to the vehicle speed V, and the operation amount of the accelerator pedal 68. Accelerator opening θacc, throttle valve opening θth, which is the opening of the electronic throttle valve, brake on signal Bon, "P" indicating the brake operation state in which the driver of the brake operating member for operating the wheel brake is operated. (Parking position), "R" (reverse running position), "N" (neutral position), "D" (forward running position) and other shift lever operating positions (shift position) POSsh, in the hydraulic control circuit 50 The hydraulic oil temperature THoil, which is the temperature of the hydraulic oil, is used.

Further, from the electronic control device 70, various command signals, for example, an engine control command signal Se for controlling the engine 12, and an engaging element are sent to each device (for example, the engine 12, the hydraulic control circuit 50, etc.) provided in the vehicle 10. The hydraulic control command signal Sat for controlling the operating state of the CB, the hydraulic control command signal Slc for controlling the operating state of the lockup clutch LC, and the like are output, respectively. This hydraulic control command signal Sat is, for example, a command signal for driving each solenoid valve SL1-SL6 that regulates each clutch pressure Pc supplied to each hydraulic actuator of the engaging element CB (that is, each set clutch). It is a drive current corresponding to the indicated pressure corresponding to the pressure Pc), and is output to the hydraulic control circuit 50. Further, the hydraulic control command signal Slc is a command signal for driving a solenoid valve or the like that regulates the LC hydraulic pressure, and is output to the hydraulic control circuit 50.

In order to realize control functions for various controls in the vehicle 10, the electronic control device 70 includes an engine control means, that is, an engine control unit 72, a shift control means, that is, a shift control unit 74, and a lockup clutch control means, that is, a lockup clutch. It includes a control unit 76.

The engine control unit 72 controls the engine 12 so that the required engine torque Te can be obtained. For example, the engine control unit 72 has an accelerator opening θacc and a vehicle speed V (automatic transmission 22) in a relationship (for example, a driving force map) that is experimentally or designly obtained and stored (that is, predetermined). By applying the output rotation speed Now and the like), the required drive torque Tdem as the drive request amount Md is calculated. The engine control unit 72 sets a target engine torque Tetgt that realizes the required drive torque Tdem in consideration of the gear stage Gn of the automatic transmission 22, and controls the engine 12 so that the target engine torque Ttgt can be obtained. The engine control command signal Se is output to the throttle actuator, fuel injection device, ignition device, and the like.

The drive required amount Md includes the required drive torque Tdem (Nm) for the drive wheels 14, the required drive force Fdem (N) for the drive wheels 14, the required drive power Pdem (W) for the drive wheels 14, and the automatic transmission 22. It is also possible to use the required transmission output torque Tome in the above. Further, as the drive request amount Md, it is also possible to simply use the accelerator opening degree θacc (%), the throttle valve opening degree θth (%), or the like.

The shift control unit 74 executes shift control of the automatic transmission 22. For example, the shift control unit 74 has the actual vehicle speed V (the output rotation speed of the automatic transmission 22 also agrees) and the accelerator opening θacc (required driving force) from the predetermined relationship illustrated by the shift map of FIG. By applying Fdem, the required drive torque Tdem, the throttle valve opening degree θth, etc.), the shift of the automatic transmission 22 is determined (that is, the gear stage Gn formed by the automatic transmission 22 is determined). The shift control unit 74 outputs a hydraulic control command signal Sat as a shift command for switching the operating state of the engaging element CB to the hydraulic control circuit 50 so as to form the determined gear stage Gn.

When the automatic transmission 22 shifts, the shift control unit 74 replaces the engaging elements involved in the shifting of the automatic transmission 22 among the engaging elements CB (that is, the engagement of the engaging elements involved in the shifting). Switching between go and release), so-called clutch-to-clutch shift. For example, in the 5 → 6 upshift from the 5th gear stage “5th” to the 6th speed gear stage “6th”, the first clutch C1 and the fourth clutch C4 are re-engaged (that is, the first clutch C1). The clutch-to-clutch shift that engages the fourth clutch C4 is executed while releasing the clutch).

The lockup clutch control unit 76 controls the operating state of the lockup clutch LC. For example, the lockup clutch control unit 76 has a vehicle speed V (output rotation speed of the automatic transmission 22 Out) in a predetermined relationship (for example, a lockup area diagram) having a lockup off region, a slip operation region, and a lockup region. By applying the accelerator opening θacc (the required drive torque Tdem and the throttle valve opening θth are also agreed), it is determined which region the vehicle is in, and the operating state corresponding to the determined region is realized. The hydraulic control command signal Slc for supplying the LC hydraulic pressure to the lockup clutch LC is output to the hydraulic control circuit 50.

For example, when the eco-mode is set, the shift lever is operated to the D range position, and the brake is not operated, the coasting driving determination unit 78 operates the accelerator pedal 68, that is, the accelerator opening θacc or the electronic throttle valve. When the throttle valve opening θth, which is the opening degree, is set to 0%, it is determined that the start condition of coasting by inertia with the automatic transmission 22 in the neutral state is satisfied, and the accelerator pedal is used for reacceleration, for example. When the accelerator opening degree θacc, which is the operation amount of 68, or the throttle valve opening degree θth, which is the opening degree of the electronic throttle valve, increases from 0%, it is determined that the coasting end condition is satisfied.

When the speed change control unit 74 determines that the coasting travel start condition is satisfied by the coasting travel determination unit 78, the shift control unit 74 puts the automatic transmission 22 in the neutral state and releases the power transmission path from the engine 12 to the transmission output gear 24. Coast the vehicle. Further, when the shift control unit 74 determines that the coasting end condition is satisfied by the coasting determination unit 78, such as when the driver depresses the accelerator pedal 68 during coasting, the shift control unit 74 determines that the coasting end condition is satisfied. Control is performed so as to establish an appropriate shift stage among the shift stages of the automatic transmission 22 and promptly generate a driving force.

Therefore, the shift control unit 74 includes a target shift stage determination unit 80, a first engagement control unit 82, and a second engagement control unit 84. The target shift stage determination unit 80 determines the actual vehicle speed V and the accelerator opening θacc when the coasting travel determination unit 78 determines that the coasting travel end condition is satisfied from, for example, the gear shift diagram stored in advance shown in FIG. The target shift stage Gm is determined based on.

When returning from coasting by depressing the accelerator pedal 68, the first engagement control unit 82 sets a synchronous rotation speed Nd lower than the actual input rotation speed Nin of the stepped automatic transmission 22 at the time of determining the end of coasting. The lowest speed side of the speed gears Gn having the gears is selected as the selective gear gear Gs, and the engaging force of the engaging element Cgs for forming the selective gear gear Gs is increased. As a result, even if the difference between the input rotation speed Nin of the automatic transmission 22 and the synchronous rotation speed Ndm of the target shift stage Gm is large, the driving force can be increased immediately after returning from coasting. The synchronous rotation speed Nd of each shift stage of the automatic transmission 22 is the rotation speed (= γ × output rotation speed Now) of the input shaft determined by the respective gear ratio γ when each shift stage Gn is established. Further, the selective gear Gs is preferably a gear between the maximum speed gear Gmax and the target gear Gm determined by the target gear determinant 80, and is on the lower speed side than the target gear Gm. It is restricted so that it does not become a shift stage.

When returning from coasting by depressing the accelerator pedal 68, the input rotation speed Nin of the automatic transmission 22 is lower than the synchronous rotation speed Ndmin of the maximum speed shift stage Gmax (for example, the eighth speed). The first engagement control unit 82 delays the selection of the shift stage of the automatic transmission 22 until the input rotation speed Nin of the automatic transmission 22 becomes equal to or higher than the synchronous rotation speed Ndmin of the maximum speed shift stage Gmax. As a result, in high-speed coasting with the automatic transmission 22 in the neutral state, the maximum speed shift Gmax is selected after the input rotation speed Nin of the automatic transmission 22 reaches the synchronous rotation speed Ndm or more of the maximum speed shift Gmax. The engaging force (brake B1) of the engaging element Cgmax selected as the shift stage Gs and forming the selected maximum speed shift stage Gmax is increased.

The second engagement control unit 84 determines that the actual input rotation speed Nin of the automatic transmission 22 has reached the synchronous rotation speed Ndm of the target speed change Gm determined by the target speed change determination unit 80. When the set determination rotation speed Nj (for example, the synchronous rotation speed Ndm of the target shift speed Gm − predetermined value α) is reached, the engaging element Cgm forming the target shift speed Gm is engaged.

For example, when the clutch C2 is engaged but the clutch C3 for 7th speed engagement is released to coast the vehicle, as shown at t1 in FIG. 6, the vehicle is coasting. When the driver depresses the accelerator pedal 68 and determines that the coasting end condition is satisfied, the target shift stage determination unit 80 first determines the shift line diagram stored in advance in FIG. The fifth speed is determined as the target shift stage Gm based on the actual vehicle speed V and the accelerator opening θacc. At the time of t1, in order to semi-engage the selective shift stage Gs, for example, the engaging element Cgs (clutch C3) for forming the seventh speed, in order to immediately obtain the driving force in response to the depression operation of the accelerator pedal 68. The hydraulic command signal of The hydraulic command signal for engaging the Cgm (clutch C1) is output as shown by the solid line. At the time of t1, since the input rotation speed Nin exceeds the synchronous rotation speed Nds of the selective shift speed Gs (7th speed), the engaging element Cgs (clutch C3) that establishes the selective shift speed Gs (7th speed) By increasing the engaging force, the increase in the input rotation speed Nin is controlled while immediately securing the driving force.

That is, as shown in the time chart of FIG. 5, by the first engagement control unit 82, the shift stage Gn of the automatic transmission 22 having a synchronous rotation speed Nd lower than the actual input rotation speed Nin of the automatic transmission 22. The 7th speed, which is the slowest speed, is selected as the selective speed Gs, and the frictional engagement force of the engaging element Cgs (clutch C3) for forming the selected speed Gs (7th speed) is It is increased and the driving force of the vehicle is immediately increased. Next, as shown at the time t2 in FIG. 5, the determination rotation speed Nj set for determining that the actual input rotation speed Nin of the automatic transmission 22 has reached the synchronous rotation speed Ndm of the target shift stage Gm is set. When it reaches, the second engagement control unit 84 eliminates the engagement element Cgs (clutch C3) whose engagement force has been increased in order to transiently obtain the driving force, and at the same time, forms the target shift stage Gm. The engaging element Cgm (clutch C1) is engaged. Since the engaging state of the remaining engaging element Cg (clutch C2) continues, the target shift stage Gm (fifth speed) is formed by engaging the engaging element Cgm (clutch C1) and the remaining engaging element Cg (clutch C2). ) Is formed. As shown in FIG. 5, as shown by the value of ^{the front-rear G (m / s 2} ) of the vehicle from the time t1 when the return from coasting is started to the time t2 when the target speed change Gm is formed. In addition, even if the difference between the input rotation speed Nin of the automatic transmission 22 and the synchronous rotation speed Ndm of the target shift stage Gm is large after returning from coasting, the driving force is immediately obtained.

Incidentally, in the control at the time of returning from the conventional coasting running which is not provided with the first engagement control unit 82, as shown in the time chart of FIG. 7, the rotation speed is lower than the input rotation speed Nin at the return time t1 from the coasting running. Since the driving force due to the engagement of the engaging element Cgs for forming the selective shift gear Gs having the synchronous rotation speed Nd is not generated, the target shift gear Gm is set from the time t1 when the return from coasting is started. ^{The front-rear G (m / s 2} ) of the vehicle up to the time of formation t2 was almost zero, and the driving force could not be obtained immediately.

FIG. 6 is a flowchart illustrating a main part of the control operation of the electronic control device 70, that is, a main part of the control operation for immediately obtaining a driving force when returning from coasting.

In FIG. 6, in step S10 (hereinafter, the step is omitted) corresponding to the coasting travel determination unit 78, whether or not the vehicle is coasting in the D range is determined by, for example, the accelerator opening degree θacc from the accelerator opening degree sensor 58. Is 0%, the brake on signal Bon from the brake switch 62 is off, the operating position POSsh of the shift lever from the shift position sensor 64 is "D", and the like.

If the judgment of S10 is denied, this routine is terminated, but if it is affirmed, whether or not the end condition of the D-range coasting running is satisfied in S11 corresponding to the coasting running determination unit 78, for example. Whether or not the accelerator pedal 68 is depressed and the accelerator is turned on is determined based on the accelerator opening degree θacc from the accelerator opening degree sensor 58. If the determination of S11 is denied, S10 or less is repeatedly executed, but if it is affirmed, S12 corresponding to the target shift speed determination unit 80 is executed.

In S12, for example, from the pre-stored shift line diagram shown in FIG. 4, the target shift is based on the actual vehicle speed V and the accelerator opening degree θac when the coasting travel determination unit 78 determines that the coasting end condition is satisfied. Determine the step Gm. When shown in the time chart of FIG. 5, for example, the fifth speed is determined as the target shift stage Gm. Next, S13-S16 corresponding to the first engagement control unit 82 is executed.

In S13, the actual input rotation speed Nin when it is determined that the coasting end condition is satisfied is compared with the synchronous rotation speed Nd of each shift stage Gn of the automatic transmission 22, and in S14, the actual input rotation speed is compared. The lowest speed side gear among the gears Gn having a synchronous rotation speed Nd lower than Nin is selected as the selective gear Gs. In the case shown in the time chart of FIG. 5, the 7th speed and the 7th speed among the 8th speeds, which are the speeds having a synchronous rotation speed Nd lower than the actual input rotation speed Nin, are set as the selected speed change Gs. Be selected. In this case, preferably, the selective shift stage Gs is a shift stage (for example, 7th speed) between the maximum speed shift stage Gmax (for example, 8th speed) and the target speed change stage Gm (for example, 5th speed). Is a condition.

Next, in S15, it is determined that the input rotation speed Nin in S16 has reached the determination rotation speed Nj set for determining that the synchronous rotation speed Ndm of the target shift stage Gm (for example, the fifth speed) has been reached. In the meantime, the engaging elements Cgs forming the selective speed change Gs (for example, 7th speed), that is, the engaging forces of the clutches C2 and C3, that is, the clutch C2 is substantially fully engaged, so that the clutch C3 The engaging force is adjusted, the driving force of the vehicle is immediately increased, and the input rotation speed Nin is changed toward the synchronous rotation speed Ndm of the target speed change Gm (for example, the fifth speed). That is, the engaging element Cgs forming the selective shift stage Gs is a rotation control clutch that controls the input rotation speed Nin. From the above, in S16, the input rotation speed Nin control is performed by the engaging element (rotation control clutch) Cgs forming the eye selection shift stage Gs.

Then, in S16, when it is determined that the input rotation speed Nin has reached the determination rotation speed Nj set for determining that the synchronous rotation speed Ndm of the target shift stage Gm (fifth speed) has been reached. In S17 corresponding to the second engagement control unit 84, it is an engagement element Cgm formed by the target speed change Gm, for example, an engagement element Cgs in which the clutch C1 is engaged and the selective shift stage Gs is formed. (It is also a rotation control clutch that controls the input rotation speed Nin), for example, the clutch C3 is released, and the target shift stage Gm is established. As a result, this control routine is terminated.

As described above, according to the electronic control device 70 of the vehicle 10 provided with the automatic transmission 22 of the present embodiment, when returning from coasting by depressing the accelerator pedal 68, the first engagement control unit 82 causes the first engagement control unit 82. Selective gear Gs having a synchronous rotational speed Nd lower than the actual input rotational speed Nin of the automatic transmission 22 is selected, and the engaging force of the engaging element Cgs forming the selective gear Gs is increased to drive the vehicle 10. Was immediately increased, and then set by the second engagement control unit 84 to determine that the actual input speed Nin of the automatic transmission 22 reached the synchronous speed Ndm of the target speed change Gm. When the determined rotation speed Nj is reached, the engaging element Cgm forming the target speed change Gm is engaged.

As a result, the engaging force of the engaging element Cgs forming the selective shift stage Gs is increased, the driving force of the vehicle 10 is immediately increased, and the input rotation speed Nin of the automatic transmission 22 and the synchronous rotation of the target shift stage Gm are synchronized. Since the target speed change Gm is formed after the deviation from the number Ndm is reduced, the input rotation speed Nin is when the driver depresses the accelerator during coasting with the automatic transmission 22 in the neutral state. It is possible to quickly generate a driving force while increasing the speed.

Further, according to the electronic control device 70 of the present embodiment, the first engagement control unit 82 is based on the actual input rotation speed Nin of the automatic transmission 22 when returning from the coasting operation by depressing the accelerator pedal 68. Among the gears Gn having a low synchronous rotation speed Nd, the gear on the slowest speed side is set as the selective gear Gs. As a result, even if the difference between the input rotation speed Nin of the automatic transmission 22 and the synchronous rotation speed Ndm of the target transmission speed Gm is large, the engaging element Cgs forming the lowest speed side gear stage set as the selective transmission speed Gs. By increasing the engaging force of the vehicle 10, the driving force of the vehicle 10 is immediately increased, and the target shift stage Gm is formed after the deviation is made as small as possible. Therefore, the automatic transmission 22 is placed in the neutral state. When the driver depresses the accelerator pedal 68 during coasting, the driving force can be generated more quickly.

Further, according to the electronic control device 70 of the present embodiment, the first engagement control unit 82 limits the selected shift stage Gs so as not to be a shift stage on the lower speed side than the target shift stage Gm. After the coasting is completed, the input rotation speed Nin can be smoothly increased toward the synchronous rotation speed Ndm of the target shift stage Gm in a short time.

Further, according to the electronic control device 70 of the present embodiment, when returning from coasting by depressing the accelerator pedal 68, the input rotation speed Nin of the automatic transmission 22 is higher than the synchronous rotation speed Ndmin of the maximum speed shift stage Gmax. In the case of low rotation speed, the first engagement control unit 82 of the automatic transmission 22 shifts until the input rotation speed Nin of the automatic transmission 22 becomes equal to or higher than the synchronous rotation speed Ndmin of the maximum speed shift stage Gmax. Delay the selection. As a result, in high-speed coasting with the automatic transmission 22 in the neutral state, the maximum speed shift Gmax is selected after the input rotation speed Nin of the automatic transmission 22 reaches the synchronous rotation speed Ndm or more of the maximum speed shift Gmax. The engaging force of the engaging element Cgmax selected as the gear Gs and forming the selected maximum speed gear Gmax is increased.

Further, according to the electronic control device 70 of the present embodiment, the target shift stage Gm is the actual vehicle speed V and the drive at the time of returning from the coasting by the depression operation of the accelerator pedal 68 from the shift line diagram stored in advance. Since it is determined based on the required amount Md, the target is determined according to the actual vehicle speed V and the drive required amount Md (accelerator opening θacc in this embodiment) from coasting with the automatic transmission 22 in the neutral state. Since the gear is switched to the shift stage Gm, the driving force can be quickly generated in response to the driver's depression of the accelerator.

Although the examples of the present invention have been described in detail with reference to the drawings, the present invention also applies to other aspects.

For example, in the above-described embodiment, the electronic control device 70 (first engagement control unit 82 of the shift control unit 74) has a shift stage (7th speed and 8th speed) having a synchronous rotation speed Nd lower than the input rotation speed Nin. The 7th speed, which is the slowest speed among the speeds), was selected as the selected speed Gs, but it does not necessarily have to be the slowest speed, and even if it is the 8th speed, it is immediately. A tentative effect can be obtained in terms of obtaining driving force.

Further, in the automatic transmission 22 of the above-described embodiment, the shift stage is switched by the combination of the engagement of the two engaging elements, but the shift stage is switched by the combination of the engagement of the three engaging elements. It may be.

Further, in the above-described embodiment, the automatic transmission 22 is not limited to this embodiment, although each gear stage Gn having eight forward stages is formed. The automatic transmission 22 may be a stepped transmission in which a plurality of gear stages Gn are selectively formed by selectively engaging any one of the plurality of engaging elements. Further, in the above-described embodiment, each gear stage Gn is established by engaging the two engaging elements, but each gear stage Gn may be established by engaging the plurality of engaging elements, and each gear stage may be established. It suffices that the automatic transmission 20 can be put into the neutral state by releasing the engaging element of any one of the plurality of engaging elements CB that are in the engaging state in Gn.

Further, in the above-described embodiment, the engine 12 is exemplified as the power source of the vehicle 10, but the present invention is not limited to this embodiment. For example, the power source may employ another prime mover such as an electric motor in combination with the engine 12. Further, although the torque converter 20 has been exemplified as the fluid type transmission device, the present invention is not limited to this mode. For example, instead of the torque converter 20, another fluid type transmission device such as a fluid coupling having no torque amplification action may be used.

It should be noted that the above is only one embodiment, and the present invention can be implemented in a mode in which various changes and improvements are made based on the knowledge of those skilled in the art.

10: Vehicle 22: Automatic transmission (stepped automatic transmission)
68: Accelerator pedal 70: Electronic control device (control device)
82: 1st engagement control unit 84: 2nd engagement control unit CB: Engagement element Cgm: Engagement element Cgs forming a target gear: Engagement element Cgmax forming a selective gear Cgmax: Maximum speed gear Engagement element Gn to be formed: Gear stage (shift stage)
Gm: Target shift stage Gmax: Maximum speed shift stage Gs: Selected shift stage Md: Drive required amount Nd: Synchronous rotation speed Ndm: Synchronous rotation speed of target shift stage Ndmin: Synchronous rotation speed of maximum speed shift stage Nin: Actual input Rotation speed Nj: Judgment rotation speed

Claims (5)

It is applied to a vehicle provided with a stepped automatic transmission having a plurality of engaging elements and forming a plurality of gears by changing a combination of a predetermined number of engaging elements among the plurality of engaging elements. In coasting running by releasing the accelerator pedal, one of the predetermined number of engaging elements is released to put the stepped automatic transmission in the neutral state, and the coasting running by depressing the accelerator pedal is performed. At the time of return, it is a control device of a vehicle provided with a stepped automatic transmission that returns from the coasting by forming a target shift stage corresponding to the vehicle traveling state, and the coasting traveling by depressing the accelerator pedal. Upon returning from the above, a selective gear having a synchronous rotation speed lower than the actual input rotation speed of the stepped automatic transmission is selected, and the engaging force of the engaging element forming the selective transmission is increased. The first engagement control unit that immediately increases the driving force of the vehicle, and the determination set to determine that the actual input rotation speed of the stepped automatic transmission has reached the synchronous rotation speed of the target shift stage. A vehicle control device including a stepped automatic transmission including a second engagement control unit that engages an engaging element forming the target shift stage when the number of revolutions is reached. The first engagement control unit uses the slowest gear among the gears having a synchronous rotation speed lower than the actual input rotation speed of the stepped automatic transmission as the selected gear. A vehicle control device including the stepped automatic transmission according to claim 1. The first engagement control unit includes the stepped automatic transmission according to claim 1 or 2, wherein the selected shift is restricted so as not to be a shift on a lower speed side than the target shift. Vehicle control device. When returning from coasting by depressing the accelerator pedal, if the actual input rotation speed of the stepped automatic transmission is lower than the synchronous rotation speed of the maximum speed shift, the first section The combined control unit delays the selection of the selected shift stage until the actual input rotation speed of the stepped automatic transmission becomes equal to or higher than the synchronous rotation speed of the maximum speed side shift stage. A vehicle control device including a stepped automatic transmission according to any one of 1 to 3. The target shift stage is to be determined from a shift diagram stored in advance based on the actual vehicle speed and the drive requirement amount at the time of returning from the coasting operation by depressing the accelerator pedal. A vehicle control device comprising the stepped automatic transmission according to any one of claims 1 to 4.

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